Lock to prevent chairs from rocking on bases



Jan. 4, 1955 H. HoPKEs R 2,693,649

Loox To PREVENT CHAIRS FROM RocxING oN BASES Filed July 28, 1950 f INVENToR.

/Venrz/ Hoy/fes.

United States Patent O LOCK TO PREVENT CHAIRS FROM ROCKING N BASES Henry Hopkes, Warren Township, Macomb County, Mich., assigner to No-Sag Spring Company, Warren Township, Macomb County, Mich., a corporation of Michigan Application July 28, 1950, Serial No. 176,415

3 Claims. (Cl. 155-72) This invention relates generally to locking means and more especially a locking means for preventing a chair from rocking on its base.

An object of this invention is to provide means for transforming a rocking chair into a straight chair.

Another object of this invention is to provide means for adjustably holding the chair in any tilted adjustable position.

Another object of this invention is to provide a locking nllvleans for preventing rocking movement of a rocking c air.

A still further object is to provide such a means which is convenient and simple to operate.

A still further object of this invention is to provide such a means which is economical to construct and which may be supplied either as original equipment or may be attached to existing chairs.

Further objects of this invention will be apparent from the specification, the appended claims, and the drawings in which drawings;

Figure 1 is a side view partially in section showing a rocking chair embodying the invention;

Fig. 2 is a view taken susbtantially along the line 2-2 of Fig. 1; and

Fig. 3 is a view taken substantially along the line 3-3 of Fig. 2.

Referring to the drawings by characters of reference, the numeral 1 designates generally a rocking chair of the type which has a base 2 adapted to rest upon a oor and a rocking chair portion 4 having a seat 6 and a back 8. The rocking portion comprises a substantially rectangular frame member having spaced side members 12 and front and rear connecting members 14 and 16 respectively. Each of the side members 12 have secured thereto the usual supporting member 18 having a downwardly facing convex surface 20 which rests upon an upwardly facing planar surface 22 of the base member 2. The base member 2 comprises spaced substantially parallelly arranged forward and rearwardly extending opposite side members 24, the upper surfaces of which form the planar surfaces 22 connected together by means of front and back transversely extending members 26 and 28. The usual springing arrangement 30 is provided to retain the chair 4 on the base 2 but permit rocking movement therebetween.

The locking mechanism comprises a link 32 pivotally carried by the base member 2 and a clamping mechanism carried by the frame member 10. The link 32 is pivotally secured by a pin 34 to one arm 35 of an L-shaped bracket 36 having its other arm 37 secured as by screws 38 to an intermediate portion of the rear cross member 28. The link 32 extends upwardly from the base member 2 rearwardly of the rear cross member 16.

The clamping mechanism is carried `by the frame member 10 and comprises an L-shaped bracket 42 having an arm 43 which is apertured as at 44 and which has welded thereto a nut 46, the internally threaded aperture 47 thereof being aligned with the aperture 44. The other arm 48 of the bracket 42 is secured to the rear connecting member 16 of the frame member 10. A shaft 50 passes through a cylindrical aperture 51 in one of the side members 12 and through an elongated slot 52 of the link 32 and through the aperture 44 and is screw-threadedly received within the aperture 47 of nut 46. The shaft 50 may be and preferably is noncircular in cross section and may be hexagonal as shown except for the portion 54 ice which extends through the apertures 44 and 47 and the slot S2 which is circular in section. At least a part of the portion 54 is threaded for threaded engagement within the nut 46. The intersection of the hexagonal portion of the shaft 50 with the round portion 54 provides a shoulder 56 against which an annular member 58 seats. The member 58 'provides a flange or abutment for clamping the link 32 against the arm 43 of the bracket 42 to prevent relative movement therebetween.

Externally of the rectangular frame 10, the shaft 50 is provided with an operating handle 60 by which the shaft may be rotated. Rotation of the shaft 50 moves the shoulder 56 and member 58 toward the bracket 42 to clamp the link 32 thereagainst. The lead of the screw threads are so chosen that a partial revolution of the shaft 50 will serve to clamp and completely unclamp the link 32. Since rotation of the shaft 50 need be only a partial revolution and to prevent accidental unscrewing of the shaft 50 from the nut 46, an arm 61 provided with a polygonal aperture 62 is slipped over the shaft 50. The aperture 62 is located off center on the arm 61 whereby the arm will strike the rear cross member 16.

lf desired a bushing 64 may be placed on the circular portion 54 of the shaft 50 between the nut 46 and member 5S to permit easy movement of the shaft upwardly and downwardly through the slot 52 when the chair is being used as a rocking chair and is not in locked position. The bushing 64 also serves to protect any of the threads which extend into the slot 52.

The locking mechanism may be easily applied to exist- Iing chairs by the provision of a single drilled hole 51 through the side member 12. After the hole 51 has been made in the side member 12, the shaft 50 with the handle 60 removed is inserted and the two brackets 36 and 42 are secured to the usual rear cross supports of the chair by means of the screws 38 and 49. The handle 60 may then be assembled on the shaft 50 and the mechanism is ready for use. Preferably the hand of the threads are chosen so'that downward forward movement of the handle serves to clamp the link 32 although it could operate reversedly.

What is claimed and is desired to be secured by United States Letters Patent is as follows:

l. A locking device for a rocking chair having a base portion and a seating portion which rocks on the base portion, said locking device including a link having an elongated slot therein, means for pivoting one end of said link to one of said portions, a bracket securable to said other portion having a threaded aperture aligned with said slot in the link, a shaft of polygonal section supportable for rotation by said other portion, said shaft having a cylindrical end section forming a shoulder, said cylindrical end section extending through the slot in the link and having a thread mated with the thread of the aperture in the bracket, and a washer on said cylindrical end section abutting against said shoulder and engageable with the side of the link opposite to that engageable by said bracket whereby when the shaft is rotated in one direction the link is locked between the bracket and washer.

2. A locking device for a rocking chair as recited in claim l, including an arm having an aperture the shape of the shaft section through which the shaft extends in nonrotatable relation thereto, said arm being in a position to abut said other portion of the rocking chair when said shaft is mounted thereon for limiting the degree of rotation of said shaft.

3. A locking device as recited in claim 2, including a handle having a recess the shape of the shaft section which extends therein when the handle is attached thereto in nonrotatable relation therewith.

References Cited in the file of this patent UNITED STATES PATENTS 130,554 Wiggers Aug. 13, 1872 687,235 Ingells Nov. 26, 1901 1,095,890 Knauer May 5. 1914 1,244,389 Stockwell Oct. 23, 1917 2,524,418 Belisle Oct. 3, 1950 2,541,744 Burton Feb. 13, 1951 

